To assist in the teaching of Rural Science, a glass-house from Brittas Castle was purchased for the school in 1939. It was purchased after the Castle had burnt down. Instruction and demonstrations were given in the glass-house. The school garden was very much part of the school. The Caretaker was Mr James Young and he worked diligently all-year round in the garden.

During the War Years, 1939-1945, the national aims of self-sufficiency and tillage were reflected in the school curriculum in Clonaslee. A programme was developed to assist students to grow their own vegetables and to provide information to young farmers in tillage farming. Seed-testing and analysis services were provided by the school to the local farmers of the area.

Domestic Economy Evening Classes were popular during the War Years. Miss O’Callaghan was appointed as Domestic Economy Instructress. She provided Emergency food lectures and demonstrations.

Farm Discussion Groups as well as a series of R.D.S. and Barrington Lectures were held in Clonaslee Vocational School in the 1940s and 1950s on topics such as “The Making and Management of Pastures”, “Trees and Tree-Planting in Ireland”, “Education as a Factor in Agricultural Production”, “Farm Buildings”, “Out of Season Grass”, “Fodder Beet”, etc.

A variety of scholarships were awarded to students of Clonaslee Vocational School from the 1940s onwards in Irish, Rural Science, Commerce and Hotel Cookery.
Clonaslee students were frequent winners of the Home Garden Prizes which were awarded each year by County Laois V.E.C. Students, assisted by the Rural Science teacher, were required to cultivate plots at their own homes and grow garden vegetables.

Attendance in the school was poor in September, October and in the Spring-time of each year as many students stayed at home to do farm-work. The Day Vocational Group Certificate syllabus was introduced in 1947. It was designed for students in vocational schools who undertook subjects such as Woodwork, Metalwork, Domestic Economy, Rural Science and Commerce. Gradually parents saw the value of this exam and attendance began to improve. A strong commitment to vocational education developed in the Clonaslee area. The Group Cert became the entry requirement for apprenticeships. Many of the Clonaslee students progressed to apprenticeships with the E.S.B., Bord na Mona, Post and Telegraphs, the Army Training School and the Air Corps.

The school was involved in starting the ICA in the mid-40s. The ICA and Macra na Feirme started the Clonaslee Show in 1948. The Junior Farmers’ Club was established in Clonaslee Vocational School in the early 1950s and carried out a wide-variety of farm and house-related projects, tours, talks, film shows, question-time, etc. Students were interviewed on Radio Eireann about their activities in 1957, students represented the club at Shows, in Competitions, etc. Some members of the Farmers’ Club and Macra na Feirme started the Clonaslee Co-Operative Society in 1963 and established a pig factory station and dairy farm.

In 1955, the Forestry Course began in the school. Clonaslee Vocational School was chosen as it was close to Kinnity Castle which was the Forestry Training School at the time. The trainees travelled by bus each day to Clonaslee and back to Kinnity. They studied Woodwork, Mechanical Drawing, Maths and Rural Science. It continued until 1980 with numbers of up to forty students enrolled each year.

In the 1960s, there was an acute shortage of accommodation in Clonaslee Vocational School and rooms had to be rented in a new house across the road from the school. A Bantile-style building was built in 1967 with three classrooms, one of these rooms was converted into a Science Room.

In 1967, free second level education and free bus transport boosted the numbers in the school. The Intermediate Certificate Exam was offered in Clonaslee in 1968. This led to an increase in the subjects offered to students and included History, Geography, French, Religion, English, Irish, Maths, Science, as well as the traditional practical subjects. Latin was also taught in the school.

Mr Fran Bates became the new principal in 1978 when Mr P.D. Brickley retired. The school got its first computer, an Apple 2 in 1982 and programmes used by the students were “Little Brick Out” and “Animals”. The Outdoor Pursuits’ Centre opened in 1983, it was designed by Mr Des Dillon, retired teacher and Mr Pat McGourty, Woodwork teacher.

The Leaving Certificate was offered to students in 1987. This led to an increase in staff and students. Students were offered Higher Level in eight Leaving Certificate subjects and exam results have been exceptional each year. Prefabs were added, the Outdoor Pursuits’ Centre and local Community Centre were also used by the school.